Jose Carlos Garcia Jr.1*, Eliana Aparecida de Rezende Duek2, Renan Pelluzzi Cavalheiro3, Helena Bonciani Nader4 and Edna Frasson de Souza Montero5
1NAEON Institute, Sao Paulo, Brazil
2Pontifical Catolic University of São Paulo, Brazil
3Federal University of São Paulo, Brazil
4University of São Paulo, Brazil
Background: The use of membranes has been reported to present a positive impact on tendon healing. Thus refinements in absorbable materials and the best knowledge of the reparative process are important to drive clinicians into choose the more suitable therapeutic options. Hypothesis/Purpose: Membranes presenting low crystallinity within an elastic structure may result in more biocompatible materials, improving healing at the same time that minimizes side effects related to the absorbable materials. Study Design: It is a preclinical prospective randomized case-control study using animal model (New Zealand rabbits). Methods: This study assessed the effectiveness of a new absorbable membrane that possesses mechanical and chemical features more suitable to tendons. The 46 rabbits underwent tenotomy and reconstruction of the right gastrocnemius tendons. They were randomly divided into three groups: case group (tendons wrapped with a membrane), control group, and intact tendon group. Animals of both the groups were allocated for extraction at seven, 14 and 28 days. Macroscopy, glycosaminoglycans, type I collagen (through polarized light) and histologic assessments were performed. Statistical tests respected the nature of the data in an adaptive model. Results: At 14 and 28 days, the tendons of the case group presented less adherences (p=0.02 and p=0.03, respectively). Glycosaminoglycans (GAGs) presented statistical differences only for the central part of the tendon for Dermatan Sulfate and Hyaluronic Acid, both for the 7th day assessment p=0.02 and 0.04 respectively. Chondroitin Sulfate in the same part of the tendon presented a difference p=0.05. At 14 days, there was equivalence between the samples for CS and DS p>0.39. The modified histologic Watkins classification for case and control groups averages: 14.67 ± 0.42 and 12.67 ± 0.56 (p=0.03) at 14 days, and 19.88 ± 0.83 and 17.25 ± 0.62 (p=0.02) at 28 days. The mean of gray value for codified red color on Image-J® for type I collagen were 2.41 ± 0.33 and 1.31 ± 0.18 (p=0.01) at 14 days, and 7.30 ± 0.63 and 2.92 ± 0.32 (p<0.0001) at 28 days. Conclusion: These results suggest that the tendons wrapped with the new membrane presented changes that facilitated the healing process of the gastrocnemius tendons of New Zealand rabbits.
Jose Carlos Garcia Jr., de Rezende Duek EA, Cavalheiro RP, Nader HB, de Souza Montero EF. Effects of Elastic High-Molecular Weight Poly (L-Co-D, L Lactic Acid) with 1,3-Trimethylene Carbonate Membrane in the Expression of Collagen and Glycosaminoglycans Tendon Healing, A Randomized Controlled Trial in Rabbits. Clin Surg. 2020; 5: 2860..